Lifting jack



Feb. 21, 192s. 1,659,785

C.J.RODMAN ETAL LIFTING JACK J Filed April 26. 1926 2 SheetS-Sheei l Feb. 21, 192s.

C. J. RODMAN ET AL Filed April 26. 1926 LIFTING JACK 2 Sheets-Sheet 2 ggd/ventole:

@aff-7 lo readilyI eitendedl Patented Feb. 21, 1928.

UNI"reor STATES errlice. j

CLARENCE J. RCDMAN AND CLEMENT .'T.

THE BUCKEYE JACK MANUFACTURING CoisfrrArIY,l or ALLIANCE, CHIC, A Con'- PORATION" OF OHIO.

BATES, jor` ALLTANCny 01110, Assienons To LIFTTNG' JACX Appucatmn filed Aprlvze, lees. serial-n1104514;

This inventionl relates to a/ multiple lift jack of that type wherein a plurality of screws are employed and are arrangedtoj act-| simultaneously to effecty a mafziilnuih' lift morey than twic'ethe heightfofy the closedjjacl. Our object is tov'provide suchga' in a simple and efficient form,y which maybecheaply manufactured, shall he" very'corhpact when closed and may be Our invention is here# irlafter more fully explained in connection with the drawings, which illustrate a preferred embodiment thereof, and its essential characteristicsk are summarized in vthe claims. Y v

I nt-he'drawihg's Fig'. 1 is al vertical central section' of one 'form of our jack collapsed;A Figi Quis a` plan thereof, partly broken'rawayiglliig. 3 isa vertical central sectionin' a' plane at right angles toj Fig. 1

(as indicated'by the line 3-3 thereon) showsection' on theline'leel'of Fig.V '1;

`The particular embodiment shown in the drawing cdprises essentially five'members as' follows;V

First': A basel member, as'11, rigidly'carrying anupstgancling hollow screw 10,A with exterri'al threads' 12,' and' rigidly Carrying larounds ucli sorew and some distance beyond Second: A screw 2O having `external threads inf the reverse direction from the threads 12 o'f the screw 10, this inner screw being' of' smallerA diameter andi slidably sliding' freely within the bore of the screw'lOfv Third; fsleeve' S'Oh'aving aA head portion 31 internally threaded to engage the threads 21'I of the screw 201 andv h'alvi 11` g"al skirt portion dependiiigbetveen the stationary screw11 and the" guiding member 14, and provided' adjacent its' lower endwithtlirefads toerigge the' stationary screw 10. The head 3 1 isfo'riielcl withY a suitable: gear 35 wherebythe" sleeve may be: driven'. Foiir'th A ro'tattab'ley 'ili"ivi'1`1g"',pirildnV 40 mesh with thege'ar 35,' and having" suit? abl` reanshy" which it" maybe rotated;

Fi, h: shitable housingf` 5 0 providing bearing for the pinion' L1(), ano the gear 35 and hayiiiga depending.' skirt` 52 which' telese; es with the guiding member 14;; the aiid guiding member preveritingN the housing rotating while allowingl it to rise a'sf the jack vis extending.Y The housing has'a lugoccupying a keyway 25 in the screw 20.

It followsVV from the above described'construction thatv the drivingl pinion l10 isl in a fixed angular position with' reference to the base butV stands at various elevations.

member itselfV will-A rise ori-'the stationary screw 1Q,"- thus giving a double lift' to the upperendS ofl theV screw or toa load saddle 23 mounted thereon. ,A limity of extension may be readily provided bymea'rs of a pin 27 cairied' bylltheY innermost' screw, which pin engages the underside ofl the driving sleeve member at the uppermost position of the" screw. This uppermost vposition of the screw 2O with-refereiice to thesleeve membepis aceofpaied' by Substantially the uppermost .position of the slee've memberBO with reference'to theV stationary screw 10,? as shown in" 'Fig 3.

I t is essential that the direction of threadihg. of tlfle, stationary Screw 10 be opposite to 'that' of the movable screw 20, one being a right hand thread and the-other' a left hand thread.v VVefhaVe shown the stationary screw as' having the'right hand thread rand the trav-v elihgserewthe lefthand dread; but of @ourse this condition could be reversed.' Likewise the pitchof the screws may be the same in degree, or different ify desired. If different, 'the screwl with the steeper pitch will have a greater travel, than the screw of lesser pitch, for a-V givenrotation" yof the driving sleeve. Bymakiag; the innermost screw of Slightly steeper pitch,- weare enabled to' cause@ it to liftv amount' substantially the: same as the heightof thel stationary-screw while Vthe sleeveflif-ts a? sin'ilaan'n'ou-n't-v reduced by theheight of the threaded region adjacent the lower end of the*sleeve.` This"i is the operation illu.strated in thev` dra-wings, but, as'fstated, therelatioof the degree of pitch of thetiivo` s'crwsmay" be" varied ifA desired,

In the drawings, we have shown the screw l as formed integrally with the base 11 and we have shown the stationary guiding niembei' as a sleeve le riveted to the base by means of integral tongues l of suoli sleeve. rThis particular way ot' connecting all these rigid parts may be varied as desired. They can all be cast as a unit, or the sleeve ll might be integral with the base and the screw l0 made separate and secured in position.

We have also shown a base plate 1S inset in the basell and covering the bore ot the stationary screw, lthis plate being secured to the saine riveted tongues l5 which hold the guiding .sleeve lei. f The guiding sleeije 14- and the skirt 52 ot the housing are shown as hexagonal tubes, this being a convenient form of a non-circular member, allowing the. telescoping `while preventing rotation.

As shown, the housing 50 is' a two partmember diametrically separable and held 'together in practice by bolts 56. The tube 52 is shown as provided at its upper .end with an outwardly extending flange 57 which oceupies an annular recess in the housing.

The driving pinion member 40 is 'shown as provided with a cylindrical shank occupying the bearing provided by the housing members and having a collar/i6 beyond that housing, the pinion itself beingsubstantially at the inner face ot the housing.

In assembling the parts, the base member, the stationary screw, the stationary guiding .sleeve and the lclosing base plate 18 may all be rigidly formed before such assemblage.

l The stop pin 27 may be put in placein the screw Q0, and then this screw, with its load saddle removed, inserted from the bottom upwardly into the head of the rotatable sleeve member and thereafter the saddle applied.

Now, the housing skirt 52 may be dropped into position outside of the guiding sleeve lll; then the rotatable sleeve member carrying the inner screw screwed down to itsr lowerniost position on the stationaryscrew, as shown in Fig. l:V then the linner sci'ew if it isr not already at the bottom, rotated to that position; thereafter one-half of the vhousing 50 isapplied, the pinion is put in place in such one-halt in mesh with the gear and then the other one-halt of the housing is installed, the screw 20 being positioned so that the housing lugs 55 occupy the keyways 25. Now, the bolts 56 put into place andthe iiutstighteued. vvllheii the two halvesk ot' the housing are thus bolted together, they provideproperwbearings .tor the gear 35 and for the driving pinioirtO'and also tightly clamp the `depending skirt 52.

llt will beseeiiit'roin an inspection of Fig. l

vthat ourY jack is extremely compact, there being very little waste space over` the theoretic minimum; likewise in its extended posi tionv the jack closely approximates themaxin'iun'i'theoretic extension. i .f

Hai/'ingvthus described our invention', we claim:

l. .ln a ack of the character described,tlie

combination oi a base, ahollow externally threaded screw rigidly-carried thereby, a second externally threaded screw freely slidablc within the bore ot the stationary screw, a

sleeve embracing said screws and threaded Y at the lo wei' end on the stationary screw and at the upper end on the traveling screw, a gear on said sleeve, a pinion meshing with the gear, a housing carrying the pinion and telescoping sleeves vsui-roiiiiding the screws and forming al connection between the housing and Vthe base, means for preventing the housing sleeve rotatingon the base sleeve,

and means forpreventing lthe -second .screw rotating with reference to the housing.v

2. In a` j ack ot' the character described, theVY combination ot a base, a hollow externally threaded screw rigidly carried thereby, an eX- tei'nally threaded screw freelyslidablewithiii the bore of the stationary screw, a sleeve embracing said screws and threaded. at the lower enden the stationaryscrew andv at the upper end on vthe travelingscrew, Idriving mechanism Vlor the sleeve mounted in a housing, `telescoping sleeves surroundingA 'the lill) threads of the two screws being of opposite direction, a rotatable sleevev having a portion occupying'the space between the `,stationary screw andthe stationary sleeve, Vsaid sleeve having a threaded engagement near the lower end with the stationary screw Vand at the upper end witlilthe traveling screw,

llO

mechanismfor rotating said sleeve,a housn ing carrying said mechanism, said housing having a depending tubular skirt which telescopes with the stationary base sleeve. 'L

4. In a jack of the character described, the combination of a base,`.a hollow vertical eX- ternally threaded screwv Vrigidly mounted thereon, .a hollow sleeve. of noncircular cross-section rigidly Y.mounted on.l the base around .the stationary screws, a. traveling screw freely occupying'the bore of. the stationaryY screw, a rotatable sleeve .adapted to extend .into Vthe space between the stationary screw and the stationary. sleeve, .and

having .Hear .it/S 10W@ and threads engaging the stationary screw and near its upper end threads engaging the traveling screw, means for driving said rotatable sleeve, a housing providing bearings for the driving means, and a non-circular skirt carried by the housing and having a telescoping engagement with the non-circular stationary sleeve.

5. In a jack of the character described, the combination of a base, a hollow vertical eX- ternally threaded screw rigidly mounted thereon, a hollow sleeve of non-circular cross-section rigidly mounted on the base around the stationary screw, a traveling screw freely occupying the bore of the stationary screw, said inner screw havingfits threads in the opposite direction from those ol the stationary screw and *provided with a vertical keyway, a rotatable sleeve adapted to extend into the space between the stationary screw and the stationary sleeve, and having near its lower end threads engaging the stationary screw and near its upper end threads engaging the traveling screw andl having near its upper end a gear, a rotatable pinion meshing with said gear, a housing providing bearings for the gear and pinion, said housing having also a lug occupying the keyway in the inner screw, and a noncircular skirt carried by thel housing and having a telescoping engagement with the stationary non-circular sleeve.

6. In a jack of the character described, the combination of a base, a stationary screw carried thereby, a traveling screw adapted to telescope with the stationary screw, 'said screws khaving their threads extending in the opposite direction, a rotatable sleeve embracing and engaging with screws, mechanism for rotating the sleeve, a separable housing for said mechanism, and a sliding connection between the housing and the base of the jack comprising a stationary non-cin cular-sleeve carried by the base and a coacting non-circular sleeve carried by the housing, said non-circular sleeves surrounding the stationary screw.

In testimony whereof, we Vhereunto affix our signatures. n

CLARENCE J. RODMAN. CLEMENT J. BATES. 

